Well, my friend bought this snowmobile last year, and we were unable to keep it running. Now, we replaced everything in the carb, and cleaned it. Now, I believe that these snowmobiles are supposed to have impulse lines that run from the carb to the bottom of the crank case. This snowmobile doesnt have one, and somwhere I heard that some of the Tillotson carbs dont have one. We did get a second engine when we bought the snowmobile, and that has a fitting in the gasket that connects the carb to the engine. This fitting is not on the engine in the snomobile right now. I dont know what to think. I cant figure out what is going wrong. What do you guys think? Where could I find a gasket with the fitting in it?